1. Field of the Invention
The present invention relates to an attachment structure for a trim and a glass run. The trim is attached to a flange formed on the inner circumference of a window frame of a vehicle, and the glass run is attached to a door sash of the window frame so that the glass run guides a door glass to make the door glass slide on the glass run when the door glass is opened and closed in a window opening of the window frame. The present application is based on Japanese Patent Application No. 2000-43189, which is incorporated herein by reference.
2. Description of the Related Art
In the background art, a window frame of a side door of a vehicle is constituted by an inner panel, an outer panel and a door sash which are formed by press forming. To connect these members, flanges formed on the respective members are welded with each other. It is necessary to cover those flanges with a trim having a U-shaped section. A glass run to be attached into an attachment groove of the door sash is of an integral type in which the sectionally u-shaped trim is formed integrally, and others are of a separate type in which the glass run and the trim are formed separately.
In the case of the former, that is, in the case of the integral type, as shown in FIG. 11, a window frame 13′ is constituted by an inner panel 15′, an outer panel 16′, and a door sash 17′ attached between the inner panel 15′ and the outer panel 16′. A car-interior-side (hereinafter, simply referred to as “interior”) flange 17a′ of the door sash 17′ is welded with an inner-peripheral flange 15b′ of the inner panel 15′ in a condition that they are superimposed on each other. A car-exterior-side (hereinafter, simply referred to as “exterior”) flange 17b′ of the door sash 17′ is welded with a flange 16f′ of the outer panel 16′ in a condition that they are superimposed on each other. A glass run body 31a′ of a glass run 31′ is attached into a channel-like attachment groove 17c′, which is formed in the door sash 17′ by press forming. A door glass 14′ is inserted between seal lips 31b′ and 31c′ of the glass run body 31a′ so that the door glass 14′ can be guided by sliding on the glass run body 31a′. A trim 31d′ having a U-shaped section is formed integrally with the glass run 31′ so as to cover the interior flanges 15b′ and 17a′. In addition, a holding lip 31e′ also having a seal function is formed on the exterior side wall of the glass run body 31a′ so as to perform sealing between the glass run body 31a′ and a molding provided separately so as to cover the outside of the flange 16f′ of the outer panel 16′ (see Japanese Patent Publication No. JP-A-10-86668).
On the other hand, in the case of the latter, that is, in the case of the separate type, as shown in FIG. 12, a window frame 13″ is constituted by an inner panel 15″ and an outer panel 16″. A separate retainer frame 32″ (corresponding to the door sash 17″) also serving as a molding is attached to the outer panel 16″ by a clip 33″. Then, a glass run 31″ is attached into the retainer frame 32″. Meanwhile, a trim 34″ formed separately from the glass run 31″ and having a U-shaped section is attached to interior flanges 15b″ and 16f″ of the inner panel 15″ and the outer panel 16″ (see Japanese Utility model Publication No. JP-U-4-130514).
Since the trim 31d′ is formed integrally with the glass run body 31a′ in the former attachment structure for the glass run 31′, the number of parts can be reduced. However, the glass run 31′ increases in size as a whole so that there is a problem in the working of attachment to the window frame 13′. In addition, the interior flanges 15b′ and 17a′ of the inner panel 15′ and the door sash 17′ respectively perform sealing between the window frame 13′ and a door weather strip provided at a door opening edge of a vehicle body frame, at the inner peripheral edge of a corner portion of the window frame 13′. Accordingly, it is necessary to set the curvature radius of each of the flanges 15b′ and 17a′ to be large in accordance with the large curvature radius of a corner portion of the weather strip. On the contrary, each of the inner peripheral edges of corner portions of the outer panel 16′ and the door sash 17′ is set to have a small curvature radius in order to improve the external appearance. Incidentally, the above configuration will be made clear in FIG. 2, which shows an embodiment of the present invention.
From the point of view of realization in sheet metal working, however, it is difficult to set the curvature radius of the corner portion at the door opening edge of the vehicle body frame to be small in accordance with the curvature radius of the corner portion of the door sash 17′.
Accordingly, the glass run body 31a′ of the glass run 31′ and the trim 31d′ have different shapes in their corner portions so that each of molded portions of the corner portions has a complicated curved-surface structure and increases in size. Thus, there is a problem that it is difficult to form them by a molding method.
In addition, it is necessary to form the interior seal lip 31b′ to be large due to the integral formation of the trim 31d′ as shown in FIG. 11. Accordingly, it is difficult to balance the durability of the seal lip 31b′ with the sliding resistance when the door glass 14′ moves up and down.
Further, there is also a problem that the attachment of the glass run 31′ to the window frame 13′ is difficult in a corner portion so that it is difficult to set the glass run 31′ in a proper position.
On the other hand, in the latter separate-type attachment structure for the glass run 31″ and the trim 34″, the glass run 31″ and the trim 34″ are formed by separate members from each other. Accordingly, it is possible to form the glass run 31″ to be small as a whole, and it is also possible to mold a corner portion of the glass run 31″ easily. In addition, a corner portion of the trim 34″ can be formed only by bending an extrusion body formed by an extruding method.
In the latter attachment structure, however, the separate retainer frame 32″ is attached to the outer panel 16″. Accordingly, the retainer frame 32″ may shift in position due to an error in manufacturing and installing the outer panel 16″ and the retainer frame 32″. As a result, there arises scattering in the pressing force on a contact portion between the interior holding lip 31f″ of the glass run 31″ and the holding lip 34a″ of the trim 34″. Then, a shortage of the pressing force causes a failure in sealing, and a gap is formed so that the exterior appearance deteriorates. On the contrary, if the pressing force becomes excessive, the seal lip 31b″ of the glass run 31″ is displaced on the car-exterior-side. As a result, the seal lip 31b″ is intensely pressed on the door glass 14″ so that the sliding resistance increases when the door glass 14″ moves up and down. Thus, there is a problem that the door glass 14″ cannot be moved up and down smoothly.